Evaluation of the metastatic status of lymph nodes identified using axillary reverse mapping in breast cancer patients

Abstract

BackgroundAxillary reverse mapping (ARM) is a new technique to preserve upper extremity lymphatic pathways during axillary lymph node dissection (ALND), thereby preventing lymphedema patients with breast cancer. However, the oncologic safety of sparing the nodes identified by ARM (ARM nodes), some of which are positive, has not been verified. We evaluated the metastatic status of ARM nodes and the efficacy of fine needle aspiration cytology (FNAC) in assessing ARM node metastasis.MethodsSixty patients with breast cancer who underwent ARM during ALND between January 2010 and July 2012 were included in this study. Twenty-five patients were clinically node-positive and underwent ALND without sentinel lymph node biopsy (SLNB). Thirty-five patients were clinically node-negative but sentinel node-positive on the SLND. The lymphatic pathway was visualized using fluorescence imaging with indocyanine green. ARM nodes in ALND field, whose status was diagnosed using FNAC, were removed and processed for histology. We evaluated the correlation between the cytological findings of FNAC and the histological analysis of excised ARM nodes.ResultsThe mean number of ARM nodes identified per patient was 1.6 ±0.9 in both groups. In most patients without (88%) and with (79%) SLNB, the ARM nodes were located between the axillary vein and the second intercostobrachial nerve. FNAC was performed for 45 ARM nodes, 10 of which could not be diagnosed. Six of the patients without SLNB (24%) and onewith SLNB (3%) had positive ARM nodes. Of these sevenpatients, four had >3 positive ARM nodes. There was no discordance between the cytological and histological diagnosis of ARM nodes status.ConclusionsPositive ARM nodes were observed in the patients not only with extensive nodal metastasis but also in those with a few positive nodes. FNAC for ARM nodes was helpful in assessing ARM nodes metastasis, which can be beneficial in sparing nodes essential for lymphatic drainage, thereby potentially reducing the incidence of lymphedema. However, the success of sampling rates needs to be improved.

“Reverse axillary mapping in early stage breast cancer Is it oncologically safe? A feasibity study

“…The positive RAM node was identified in pN3 axilla(high stage axillary disease). The same pattern had been described in various studies in literature, which have shown a positive relation between high nodal positivity and chance of arm lymphatics also being involved by the disease [9,10,17,19,20] Schunemann Jr et al, found a statistically significant association between occurrence of metastasis in RAM nodes and high nodal disease(P<.0.001) [19]. Most studies thus suggest that performing RAM in patients with high nodal disease, is not oncologically sound [10,11,17,19] .…”

“…In our study, using methylene blue dye injection, at the start of surgery, blue lymphatics were identified in72.2 % while blue lymph nodes could be identified in 61.1%.The pattern of distribution of arm lymphatics in axilla varies with respect to axillary vein . Bonetti et al described 5 common variations in the distribution of arm lymphatics in the axilla [6], with most of the lymphatics and lymph node being found within the region formed by inferior margin of axillary vein and the second intercostobrachial nerve and thoraco dorsal pedicle [4,5,11,17].In our study, 69.2% of the identified arm lymphatics was within one cm inferior to axillary vein, lateral to thoraco dorsal pedicle.RAM lymphatics were successfully identified in 10 of 13 patients with negative axilla, in 2/2 patients with pN1 disease but only in 1/3 patients with pN3 disease. This may be postulated to be secondary to lymphatic obstruction by extensive disease in axilla as described in literature [9,18] .…”

“…They also found no discordance between the FNAC and final histopathology report. [17] Use of blue dye injection (injection in the arm) has been found to be associated with few local morbidity, though no systemic reaction has been documented in literature. Nos et al , described persistent blue tattooing in the arm in more than 50% of patients at a median follow up of 21 months, while Bedrosian et al, described a more milder reaction.…”

“…A number of techniques have been described in literature for the identification of arm lymphatics in the axilla, using blue dye [4,6,8], radio isotope [9] and fluorescence [17]. Rate of Identification of arm lymphatics varies from 33.3% in initial studies to as high as 91% with use of radio isotopes, [8,9].…”

Anatomy of the Lymphatic Drainage of the Upper Limb and Breast and its Role in Lymphedema Prevention after Breast Cancer Treatment

“…Some showed a positive view of the benefits and morbidity reduction by using this technique, even though further studies are necessary to affirm anything (Gobardhan et al, 2012) others defend the use of this technique in all cases, except in patients whose sentinel lymph node (SLN) is too close to the ARM lymph node and when there are too many compromised nodes (Boneti et al, 2009) and there are some who question the real effectiveness and therapeutic safety of this technique (Ikeda et al, 2012).…”